<?php
$this->title = 'My Yii Application';
?>
<div>
    <form enctype="multipart/form-data" method="post" action="/system/upload">
        <input type="hidden"  name="<?= \Yii::$app->request->csrfParam; ?>" value="<?= \Yii::$app->request->getCsrfToken();?>">
        <input type="file" name="attachmentUploader">
        <input type="submit" value="submit">
    </form>
</div>
